How fast will local models feel on the Mac Studio M5 Ultra 512GB?

Local LLM speed on the Mac Studio M5 Ultra 512GB

The Mac Studio M5 Ultra 512GB has 512 GB of unified memory and 1200 GB/s of memory bandwidth, which is what mostly decides generation speed. Below is the expected speed for each model at the best quantization that fits.

ModelQuantizationMemoryGenerationFirst token
Qwen 3.6/3.8 27BQ4_K_MFits34 tok/s0.4 s
GLM-5.3 FlashUD-Q4_K_XLFits51 tok/s0.3 s
GPT-OSS 20BMXFP4Fits272 tok/s0.3 s
Gemma 4 26B A4BQ4_K_MFits227 tok/s0.3 s
Qwen 3.5/3.6 35B A3BQ4_K_MFits307 tok/s0.3 s
Ornith 1.5 35B A3BQ4_K_MFits313 tok/s0.3 s
DeepSeek V4 FlashUD-Q4_K_XLFits85 tok/s0.3 s
GPT-OSS 120BMXFP4Fits205 tok/s0.3 s
Gemma 4 31BQ4_K_MFits31 tok/s0.4 s
Llama 3.1 8BQ4_K_MFits115 tok/s0.3 s
Qwen 3.5 9BQ4_K_MFits100 tok/s0.3 s
DeepSeek R1 Distill 14BQ4_K_MFits63 tok/s0.3 s
Ornith 1.5 9BQ4_K_MFits98 tok/s0.3 s
Muse Glimmer 30BQ4_K_MFits29 tok/s0.4 s
Qwen3 30B A3BQ4_K_MFits282 tok/s0.3 s

Other hardware

Estimates for a short prompt on a single device. Measured numbers come from community benchmarks (r/LocalLLaMA, localscore.ai and more); others are derived from similar setups or projected from specs. Open source on GitHub.